Find the sine of an angle given in degrees.
How it works
The sine function returns the ratio of the opposite side to the hypotenuse in a right triangle for a given angle. sin(30°) = 0.5; sin(90°) = 1, its maximum value.
What this does not include
This is distinct from this site’s inverse sine (arcsin) calculator, which goes the opposite direction — from a sine value back to an angle, rather than from an angle to its sine value.
How to use this calculator
- Enter an angle in degrees.
A worked example
sin(30°) = 0.5.
sin(90°) = 1, the maximum value sine ever reaches.
What the variables mean
| Variable | Meaning |
|---|---|
| Angle | Input angle, in degrees |
| Result | The sine of that angle, always between −1 and 1 |
Edge cases worth knowing
Sine never exceeds 1 or drops below −1, regardless of the input angle — a useful sanity check, since any result outside that range signals a calculation error somewhere else, not a valid sine value.
Sine is periodic — many different angles share the same sine value (30° and 150° both give 0.5), so knowing the sine alone doesn’t uniquely identify the original angle.
What’s the range of possible sine values?
Sine always returns a value between −1 and 1, regardless of the input angle, since it represents a ratio of triangle sides that can never exceed the hypotenuse’s length.
Why does sine repeat every 360°?
Because 360° represents one full rotation around the unit circle, after which the angle points in exactly the same direction and produces the same sine value again.
What’s the sine of a negative angle?
Negative — sine is an odd function, meaning sin(−θ) = −sin(θ), reflecting the symmetry of the unit circle above and below the x-axis.
